检索结果-南通市图书馆

Power Quality Assessment of Voltage Positive Feedback Based Islanding Detection Algorithm

Journal of Modern Power Systems and Clean Energy 2020年第4期8卷 787-795页

作者： reza bakhshi-jafarabadi reza Ghazi Javad Sadeh Electrical Engineering Department Faculty of EngineeringFerdowsi University of MashhadMashhadIran

Islanding refers to a condition where distributed generators(DGs)inject power solely to the local load after electrical separation from power *** islanding detection methods(IDMs)categorized into remote,active,and passive groups have been reported to detect this undesirable *** active techniques,a disturbance is injected into the DG’s controller to drift a local yardstick out of the permissible *** this disturbance leads to more effective detections even in well-balanced island,it raises the total harmonic distortion(THD)of the output current under the normal operation *** paper analyzes the power quality aspect of the modified sliding mode controller as a new active IDM for grid-connected photovoltaic system(GCPVS)with a string *** performance is compared with the voltage positive feedback(VPF)method,a well-known active *** evaluation is carried out for a 1 k Wp GCPVS in MATLAB/Simulink platform by measuring the output current harmonics and THD as well as the efficiency under various penetration and disturbance *** output results demonstrate that since the proposed disturbance changes the amplitude of the output current,it does not generate harmonics/***,it has a negligible adverse effect on power *** is finally concluded that the performance of the sliding mode-based IDM is reliable from the standpoints of islanding detection and power quality.

关键词： Islanding detection method(IDM) power quality sliding mode controller total harmonic distortion(THD) voltage positive feedback(VPF)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Determination of fiber length and juvenile and mature wood zones in Acer velutinum *** grown in Iran

引用

Forestry Studies in China 2012年第4期14卷 323-326页

作者： Majid KIAEI reza bakhshi Samane VEYLAKI Department of Wood and Paper Science and Technology Chaloos BranchIslamic Azad University

In our investigation we studied fiber lengths and the transition age from juvenile to mature wood in Acer velutinum Boiss. For this purpose, samples from three normal maple trees at a Noshahr site in northern Iran were selected. Disks were cut at breast height. Test samples were taken along a radial direction from the pith to the bark, accounting for every ring during a 48-year period. We used the Franklin method to distinguish between fibers of juvenile and mature wood. The results show that the fiber length in- creased along the radial direction from the pith to the bark. The transition age between juvenile and mature wood was determined at the 14th annual ring from the pith.

关键词： Acer velutinum Boiss. transition age juvenile wood mature wood fiber length

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Larvicidal Properties of Botanical Extracts of <i>Lawsonia inermis</i>against <i>Anopheles stephensi</i>

引用

Advances in Infectious Diseases 2014年第4期4卷 178-185页

作者： Hasan bakhshi Mohammad reza Abai Gholamreza Amin Rasoul Zolfi Masoumeh Pirmohammadi Azam bakhshi Fakhredin Taghinezhad Seyed Hasan Moosa-Kazemi Department of Medical Entomology & Vector Control School of Public Health Tehran University of Medical Sciences Tehran Iran Department of Pharmacognosy Faculty of Pharmacy Tehran University of Medical Sciences Tehran Iran Department of Nursing School of Nursing and Midwifery Qom University of Medical Sciences Qom Iran School of Nursing and Midwifery Islamic Azad University Medical Sciences Branch Tehran Iran

The aim of this study was to determine the larvicidal activity of Lawsonia inermis against Anopheles stephensi as the main malaria vector in Iran. This study was carried out from February to July 2011. Larvicidal activity of >L. inermis was studied in the range of 4 - 4000 PPM in the laboratory against early and late stages of larvae of An. stephensi. The larvae were reared in the?insectarium. The LC50 and LC90 values of the larval stages of An. stephensi were calculated by probit analysis and regression line draw using Microsoft office excel 2003 software. The highest toxic effect of L. inermis was found at 4000 PPM and the lowest at 4 PPM against larval stages I and II. The same result was found against larval stages III and IV. The LC50 and LC90 was found as 413.8 and 3366.3 respectively against larval stages I and II while against late stages found as 696.9 and 3927.7 respectively. This study suggests that L. inermis extract can be used as an alternative larvicidal compound during the IPM programs for the An. stephensi control. It is recommended to investigate the competency of other similar plants to malaria control.

关键词： Anopheles stephensi Lawsonia inermis Larvicidal Properties

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Sequence Stratigraphy of Lower Carboniferous Rocks in bakhshi Section, East-Central Iran

引用

Open Journal of Geology 2017年第2期7卷 200-211页

作者： Soheil Erfani Mohammad Hossein Adabi Mahmood reza Majidifard Nader Kohansalghadimvand Bibihaniyeh Emraninasab Department of Geology Islamic Azad University North Tehran Branch Tehran Iran Department of Earth Sciences Shahid Beheshti University Tehran Iran Research Institute for Earth Sciences Geology Survey of Iran Tehran Iran

The deposits of Lower Carboniferous rocks in Kalmard Block are characterized by Gachal informal formation, showing various properties in different outcrops. These deposits (in Gachal formation) are composed chiefly of carbonate, evaporite and siliciclastic rocks. This formation commonly hosts 190 m sandstone, limestone, dolomitic limestone and dolomite as well as a small amount of shale and marl in the bakhshi section. It unconformably underlies Devonian deposits (Rahdar formation) while lateritic soils of lower Permian (Chili formation) are depicted overlying an erosional unconformity above this formation. The mixed carbonate-evaporite-siliciclastic sequence of Gachal formation is made up of three third-order depositional sequences, separated from each other by Type 1 sequence boundary (SB1). Siliciclastic and evaporite deposits include LST system tract, whereas carbonate microfacies involve TST and HST system tracts, separated from each other by MFS. The depositional sequences identified in Gachal formation point to the Lower Carboniferous age, conforming to upper Kaskaskia supersequence. The upper erosional boundary between Gachal and Chili formations complies with the global-scale sea level fall.

关键词： Lower Carboniferous Kalmard Block Gachal Formation Sequence Stratigraphy

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：